Previously known are several ways to connect the other bar or several bars on the side of a wooden bar. Such joints are for instance the T- or K-joint between the chord of a wooden truss or between one or more diagonals, for example U.S. Pat. No. 3,507,524, U.S. Pat. No. 1,359,399 and FR 20583315. Hereinafter the connection pieces are called chord and diagonal, although the applications of the new joint are not restricted to trusses, with which, for instance, the said terms are connected. Essential in such a joint is what kind is the joint cutting of chord. This cutting is done with a cutting tool so that in the chord between the ends of the cutting area one or more grooves or fingers are formed in the chord direction. As to its breadth the cutting area can be as broad as the whole chord or only a part of it. Present joints have various problems:                wood is cut unnecessarily so, which weakens the firmness of the wood.        For the part prior chords are cut symmetrical, e.g., GB 1359399 and U.S. Pat. No. 3,702,050, which is not optimal concerning the firmness, since the tensions are divided into the joint almost always asymmetrically.        Wood is cut outside the joint area, which also reduces the firmness of the wood, e.g., U.S. Pat. No. 3,452,502.        In addition to the connection pieces nails screws, boards, etc., are needed, which add to the costs, e.g., AT 361203. The different parts of the joint are dependent of each other among others so that the cutting of one part has effect on the cutting of the other part, for instance so that the cutting of male or of the female cutting has effect on the choice of the cutting type by another cutting or so that the joint must be put together in a certain order.        The fingers are visible outside the joint, which is unaesthetical, in addition water and dirt can harmfully gather in the finger grooves.        It is not possible to use quick hardening glues, e.g., hot melt glue which sets in less than a minute, since all the prior joint bars, and in practice, the whole structure must be joined simultaneously, which would take as much time as the time it takes for the glue to harden.        By production accurate positioning of connection pieces is not easy, because the cuttings do not locate the connection pieces exactly.        The joints have discontinuities which lead to accumulations of tension and weakening of firmness, whereas an ideal firmness is obtained with a uniform tension distribution.        The cutting groove of the chord is along the grain, e.g., CA 2008043, due to which the wood splits easily along the edge of the cutting groove. In order to prevent this breaking form the cutting groove should separate as much as possible from the grain direction. A good result is also achieved so that the cutting groove is as crooked as possible.        Inside the joint there are cavities, e.g., GB 1359399 and U.S. Pat. No. 2,780,842, which make the joint weaker, because on the cavity edges peaks of tension are formed. Further, the cavities are harmful, because water can penetrate into them from the gap or cracks in the joint.        The diagonals must be installed on the side of the chord perpendicularly with respect to it or in almost perpendicular direction, which in some cases restricts the assembly of parts, for instance the assembly of a truss put together of parts. Further, the angle edge and diagonal cannot be smaller than the angle characteristic for a certain type of joint, which reduces the operational range of the joint. Before cutting of fingers the ends of bars must be shaped to be in accordance with the joint. This gives rise to costs of labour and material.        Present finger joints are not suited for making three-dimensional joints without separate connection pieces, e.g., WO 2004/094842.        